For most medical researches, animal experiments using rats or rabbits for in vivo bioassays are usually inevitable. However, as the muscle tissues of those experimental animals and those of human are after all not quite the same, it is noted that conventional animal experiments may not be able to generate accurate assessments relating to the actual condition of trauma wounds on human tissue. In addition, since the health conditions of different testing animals may be different that it is almost impossible to manually create trauma wounds of exactly the same shape and depth on those animal so as to prepare they for in vivo test, even when subjecting those testing animals under exactly the same environment, the healing of trauma wounds on different testing animals may not be the same. Therefore, it is common to waste a lot of time trying to conclude optimum healing parameters from in vivo test and thus design a therapeutic apparatuses for healing trauma wounds.
Over the past several years, vacuum-assisted closure (V.A.C.) therapy has been popularized and used as an adjunctive treatment in the management of many trauma wounds, which can help heal certain non-healing wounds by removing fluids and infectious material from the site and is applied to a special foam dressing packed in the wound cavity or over a flap or graft. In such V.A.C. system, special foam dressing with an attached evacuation tube is inserted into the wound and covered with an adhesive drape in order to create an airtight seal. Negative pressure is then applied by the use of a vacuuming pump and the wound effluent is collected in a canister. Although the exact mechanism has not been elucidated, it is evident that negative pressure contributes to wound healing by removing excess interstitial fluid, increasing the vascularity of the wound, and/or creating beneficial mechanical forces that draw the edges of the wound closer together. However, most current V.A.C. studies focus their researches upon the improvement of either the V.A.C. therapeutic apparatus itself or foam dressing packed in the wound cavity, and there is no available testing platform for clinically accessing the performance and physical properties of such V.A.C. therapeutic apparatus or foam dressing with respect to trauma wounds of different shapes and depths and under different negative pressures and different dressing. Thus, currently, there is no way of knowing how well the performance and physical properties a newly developed V.A.C. therapeutic apparatus are until it is actually being applied clinically to a test animal or human volunteer. In consequence, when it comes to the development of V.A.C. therapeutic apparatus or relating foam dressing, many efforts can be wasted in the process.